Fire extinguishing compositions, particularly for extinguishing hydrocarbon fires, must have the ability to form a film on the surface of the fuel hydrocarbon and the effectiveness of such compositions depends a great deal on the spreading ability and the spread velocity of the film over the hydrocarbon surface. Minnesota Mining & Manufacturing Company's industrial product "LightWater FC 203" is an example of a commercial fire extinguishing composition. This composition contains a mixture of a fluorinated surfactant and a non-fluorinated surfactant. This product, however, only partially spreads over cyclohexane and gasoline at low fluorinated surfactant concentrations, and spreads relatively slowly on cyclohexane and gasoline even at high fluorinated surfactant concentrations.